Antifreeze device



Dec. 4, 1945. n M. K. THOMAS 2,390,475

ANTIFREEZE DEVICE Filed Feb. 24, 1943 Patented Dec. 4, 1945 UNITEDSTATES PATENT OFFICE ANTIFREEZE DEl-JCE Mllfred King Thomas, Birmingham,Ala.

Application February 24, 1943, Serial No. 476,953

1 can. (ci. 21a-a9) This invention relates to new and useful improvements in means for preventing the freezing of pipes and likestructures.

The principal object of the present invention is to provide anelectrical device for automatically subjecting water pipes and likestructures to the application of heat when temperature drops to afreezing degree.

Another important object of the invention is to provide a device of thecharacter stated which is automatic in operation and which is of simpleconstruction and of low cost of manufacture.

These and various other important objects and advantages of theinvention will become apparent t o the reader of the followingdescription.

In the drawing: y

Figure 1 represents a front elevational view of the device.

Figure 2 is a front elevational view with the door in open position.

Figure 3 is a fragmentary vertical sectional view showing the heatingunit.

Figure 4 is a cross section on the line l-I oi' Figure 3.

Figure 5 is a vertical sectional view through the thermal switch.

Referring to the drawing wherein like numerals vdesignate like parts. itcan be seen that numeral l denotes a water pipe or the like to beprotected against freezing weather. Numeral 6 generally refers to theelectrical apparatus for automatically heating the pipe B in the eventtemperature drops to a freezing degree.

The apparatus l embodies a box l having a front door 8 and a suitablelatch 0 therefor.

The door I has an opening therethrough, through which partly projects athermostatic indicating and switching unit. This thermostatic andswitching unit is composed of a case III having a front dial Il withsuitable degree graduations thereon, this dial being visible from thefront of the door l. A shaft i2 is disposed through the case Ill andinside of the case is an anchor I3 from which extends a coiled bi-metalelement M and the other end secured to the shaft On the shaft I2, at theiront of the dial I i, is a hand I5 and on the dial Il is a contactelement i8 disposed through a bushing Il of insulation.. The contact I8in the path of the hand i5, and the contact I6 and hand Il haveconductor wires i8, i9 connected thereto.

Around the pipe 5 and within the connues of the box 1 is a heating unitgenerally referred to by numeral 20, this unit consisting of a tube ofinsulation 2l embracing the pipe 5 and around which is an electricalheating element Il. En veloping the heating element 22 and the tube 2iis a case or Jacket 23 of some refractory material, such as plaster orthe like. The conductor Il from the hand I5 is in fact a jumper whichextends to one end of the electric heating element 22, while the otherconductor I9 and a conductor 24 which extends from the other end of theheating element on the opposite sides of an electric circuit, which maybe interrupted by a plug 25, for use in conjunction with the usualcommercial electric current supply.

While the foregoing specincation sets forth the invention in specificterms. it is to be understood that numerous changes in the shape, sizeand materials may be resorted to without departing from the spirit andscope of the invention as claimed hereinafter.

Having described the invention. what is claimed as new is:

Apparatus for preventing pipes from freezing comprising a closed casingadapted for extension of a pipe into the same and having a side door. ahollow electrical heating element in said casing adapted to receivetherein a pipe extended into the casing, a thermal indicator mounted onsaid door and including an indicating hand and a heat responsive devicefor actuating the hand, a contact on said door for engagement by saidhand, and lead lines from the hand and contact to opposite sides of theheating element and arranged in said casing to be extended out of thesame when the door is open.

` MILFRED KING THOMAS.

